Talk in Kennedy circles is that Caroline Kennedy is furious over the revelation that a longtime confidant of Hillary Clinton’s secretly sabotaged her bid to become a US senator — and Kennedy may seek her revenge by backing veep Joe Biden if he runs for president.

In June, leaked emails revealed that Hillary henchman Sidney Blumenthal had orchestrated news stories undermining Caroline while she was vying to be appointed to Hillary’s Senate seat in 2008.

Pointing out that Caroline has also had to endure attacks from Donald Trump, the magazine quotes a source: “Rather than stay in Tokyo and let the politicians continue to use her as a punching bag, it would be a profile in courage for her to come home and help elect the person she believes is best qualified to lead the nation.”

Another Kennedy source tells Page Six, “Caroline may not be ready to give up a plum ambassadorship, but she will likely endorse Joe Biden if he runs. But the Kennedys always play it smart, and other members of the family will surely donate to and support Hillary.”